SMSL M500 - Owners' Thread

[vagueness]

Hi all, I just bought the M500 (HW 1.2; SW 1.4; XMOS v2.06) but have run into a weird humming issue. I hope you can help.

In lineout mode, connected via USB to a pair of KEF LSX speakers through RCA-Aux In, I'm getting a loud hum (more of a 60hz hum than a 120hz buzz). I think this is a ground-loop problem but my experience is inconsistent.

I've tried the following:

PC > USB (M500) > RCA-Aux-In (KEF LSX) – Hum

PC > iFi iDefender+ USB> USB (M500) > RCA-Aux-In (KEF LSX) – Hum (unchanged, same level)

PC > iFi iDefender+ USB+power > USB (M500) > RCA-Aux-In (KEF LSX) – Hum (unchanged, same level)

PC > USB (M500) > Headphone out – No hum

Macbook Pro (not connected to power) > USB (M500) > RCA-Aux-In (KEF LSX) – No hum

When USB is disconnected from the PC, I don't get a hum from the speakers. So it seems that the prob is the PC, yet it doesn't quite explain the lack of a hum through headphone out. And the lack of this hum when connected to the Macbook.

Using TOSLINK is not an option as my PC does not have TOSLINK out, and MQA is only supported through USB, which is the point of using this DAC.

Getting a galvanic isolator that costs more than the M500, such as the iFi nano iGalvanic 3.0, would also defeat the purpose.

Have also tried everything such as disconnecting and reconnecting everything, connecting everything to one strip, distancing the cables from power outlets etc.

Thoughts?

 

[Veri]

When USB is disconnected from the PC, I don't get a hum from the speakers. So it seems that the prob is the PC, yet it doesn't quite explain the lack of a hum through headphone out. And the lack of this hum when connected to the Macbook.

It is the schoolbook example of a ground loop over USB. It's normal the headphone out does not have it: it is when using unbalanced RCA where the problem lies. Honestly, the iFi iDefender should break the ground loop, if it doesn't it is a thrash product, shame on iFi. can you still return it?
Too bad you can't use optical input, that would solve your issues. Or XLR output to an XLR input, that would also solve your issues.

 

[Jimbob54]

Hi all, I just bought the M500 (HW 1.2; SW 1.4; XMOS v2.06) but have run into a weird humming issue. I hope you can help.

In lineout mode, connected via USB to a pair of KEF LSX speakers through RCA-Aux In, I'm getting a loud hum (more of a 60hz hum than a 120hz buzz). I think this is a ground-loop problem but my experience is inconsistent.

I've tried the following:

PC > USB (M500) > RCA-Aux-In (KEF LSX) – Hum

PC > iFi iDefender+ USB> USB (M500) > RCA-Aux-In (KEF LSX) – Hum (unchanged, same level)

PC > iFi iDefender+ USB+power > USB (M500) > RCA-Aux-In (KEF LSX) – Hum (unchanged, same level)

PC > USB (M500) > Headphone out – No hum

Macbook Pro (not connected to power) > USB (M500) > RCA-Aux-In (KEF LSX) – No hum

When USB is disconnected from the PC, I don't get a hum from the speakers. So it seems that the prob is the PC, yet it doesn't quite explain the lack of a hum through headphone out. And the lack of this hum when connected to the Macbook.

Using TOSLINK is not an option as my PC does not have TOSLINK out, and MQA is only supported through USB, which is the point of using this DAC.

Getting a galvanic isolator that costs more than the M500, such as the iFi nano iGalvanic 3.0, would also defeat the purpose.

Have also tried everything such as disconnecting and reconnecting everything, connecting everything to one strip, distancing the cables from power outlets etc.

Thoughts?

Hi all, I just bought the M500 (HW 1.2; SW 1.4; XMOS v2.06) but have run into a weird humming issue. I hope you can help.

In lineout mode, connected via USB to a pair of KEF LSX speakers through RCA-Aux In, I'm getting a loud hum (more of a 60hz hum than a 120hz buzz). I think this is a ground-loop problem but my experience is inconsistent.

I've tried the following:

PC > USB (M500) > RCA-Aux-In (KEF LSX) – Hum

PC > iFi iDefender+ USB> USB (M500) > RCA-Aux-In (KEF LSX) – Hum (unchanged, same level)

PC > iFi iDefender+ USB+power > USB (M500) > RCA-Aux-In (KEF LSX) – Hum (unchanged, same level)

PC > USB (M500) > Headphone out – No hum

Macbook Pro (not connected to power) > USB (M500) > RCA-Aux-In (KEF LSX) – No hum

When USB is disconnected from the PC, I don't get a hum from the speakers. So it seems that the prob is the PC, yet it doesn't quite explain the lack of a hum through headphone out. And the lack of this hum when connected to the Macbook.

Using TOSLINK is not an option as my PC does not have TOSLINK out, and MQA is only supported through USB, which is the point of using this DAC.

Getting a galvanic isolator that costs more than the M500, such as the iFi nano iGalvanic 3.0, would also defeat the purpose.

Have also tried everything such as disconnecting and reconnecting everything, connecting everything to one strip, distancing the cables from power outlets etc.

Thoughts?

Can you connect all components to the same wall socket (using a power strip obviously)- Im clutching at straws but I have seen others have some success doing that.

 

[vagueness]

Can you connect all components to the same wall socket (using a power strip obviously)- Im clutching at straws but I have seen others have some success doing that.

Yeah, to no avail. Anyway, I've found a workaround:

PC (USB) > M500 (Headphone out: 3.5mm-6.3mm cable) > KEF (Aux In)

 

[icsi85]

I got my M500 since 2 days! I love it! (Comming from M6 , and Xonar STX)

Info:
SW: 1.7 HW: 1.3 ; 2020-05-30

Wich driver do i need to install? Do i need to make firmware update?
Asio or Wasapi?
Grounding is needed? (It would get earthloop i think)
-------------------------
For the first 10 minutes it sounded horrible, i was sad. The highs were ear piercing, i didnt get it ...
And then playing more music with it: the bass was more extended, punchier, tight. An accousting gitar got more body, it was there in space.
Field is bigger, highs are clear, i cant stop listening all my music all over again.

I got a cheap Microlab Solo 7C speakers, i didnt listen to them to much, just for movies maybe, i didnt like the sound with M6 or STX.
I thinked the speakers are muddy, to much bass, bad stereo imaging, maybe its to big for the room, bad placing.
With M500 its great, i listen to them from now on more . Bass got controlled. It made magic!

And the earpiercing high? It went away a little bit, but i think that the headphone got more power so the headphone properties come to life.
More bass, extended, tight. I got more space, more air. The earpiercing is maybe just a thing of AKG K612 Pro

 

[Veri]

The earpiercing is maybe just a thing of AKG K612 Pro

Maybe try EQ https://www.dropbox.com/s/b4n2sjbhh1e6rnj/AKG K612.pdf?dl=0

 

[icsi85]

Maybe try EQ https://www.dropbox.com/s/b4n2sjbhh1e6rnj/AKG K612.pdf?dl=0

My wife would like your suggestion. But we all know, i need to search for a new headphone...

 

[Satyadhara]

Anyone experiencing occasional dropouts when playing MQA files? I use Roon and my core is connected to the router via Ethernet, so the connection should be stable enough... still I get short dropouts here and there.

 

[Ottacat]

Anyone experiencing occasional dropouts when playing MQA files? I use Roon and my core is connected to the router via Ethernet, so the connection should be stable enough... still I get short dropouts here and there.

I have my M500 connected to a Raspberry Pi 4 via WiFi to connect to my Roon core. My Roon core is running on an older laptop, also via WiFi. I don't get any dropouts with MQA files. I only have about 10 albums in my library, the rest is all streamed from Tidal.

 

[Satyadhara]

I have my M500 connected to a Raspberry Pi 4 via WiFi to connect to my Roon core. My Roon core is running on an older laptop, also via WiFi. I don't get any dropouts with MQA files. I only have about 10 albums in my library, the rest is all streamed from Tidal.

Thanks for sharing your experience! What are the settings for your M500 in Roon? Decoder and Renderer? Or just one of the two?

 

[Ottacat]

Thanks for sharing your experience! What are the settings for your M500 in Roon? Decoder and Renderer? Or just one of the two?

In Roon, I have the M500 enabled as Decoder and Renderer. However, because I use Roon DSP, it is Roon core that does the decode and the M500 is doing just the Render. If I turn off DSP, then Roon will have the M500 do both the Decode and Render (the signal path in Roon is so helpful). In both cases, I don't get any MQA dropouts.

 

[Satyadhara]

In Roon, I have the M500 enabled as Decoder and Renderer. However, because I use Roon DSP, it is Roon core that does the decode and the M500 is doing just the Render. If I turn off DSP, then Roon will have the M500 do both the Decode and Render (the signal path in Roon is so helpful). In both cases, I don't get any MQA dropouts.

Ok, that's the setting I use as well, albeit without DSP. Elsewhere it was suggested to me that my Roon core might get too busy streaming the MQA files, so I'll now try narrowing down the issue. Have another DAC here and still have to check if the problem occurs with this one as well. Thanks!

 

[Dexter_prog]

Hi all, I just bought the M500 (HW 1.2; SW 1.4; XMOS v2.06) but have run into a weird humming issue. I hope you can help.

In lineout mode, connected via USB to a pair of KEF LSX speakers through RCA-Aux In, I'm getting a loud hum (more of a 60hz hum than a 120hz buzz). I think this is a ground-loop problem but my experience is inconsistent.

I've tried the following:

PC > USB (M500) > RCA-Aux-In (KEF LSX) – Hum

PC > iFi iDefender+ USB> USB (M500) > RCA-Aux-In (KEF LSX) – Hum (unchanged, same level)

PC > iFi iDefender+ USB+power > USB (M500) > RCA-Aux-In (KEF LSX) – Hum (unchanged, same level)

PC > USB (M500) > Headphone out – No hum

Macbook Pro (not connected to power) > USB (M500) > RCA-Aux-In (KEF LSX) – No hum

When USB is disconnected from the PC, I don't get a hum from the speakers. So it seems that the prob is the PC, yet it doesn't quite explain the lack of a hum through headphone out. And the lack of this hum when connected to the Macbook.

Using TOSLINK is not an option as my PC does not have TOSLINK out, and MQA is only supported through USB, which is the point of using this DAC.

Getting a galvanic isolator that costs more than the M500, such as the iFi nano iGalvanic 3.0, would also defeat the purpose.

Have also tried everything such as disconnecting and reconnecting everything, connecting everything to one strip, distancing the cables from power outlets etc.

Thoughts?

Welcome to the club. I have the same issue. It IS a ground loop and my suspicion is that this DAC is the culprit. I also tried the iDfender, it change the hum a little bit when powered (but it introduces a low volume hissing noise). Frankly, I don't know what else to try, except buying a galvanic isolator which costs almost as much as the DAC.

 

[HarryDoyle]

Hello, new member here.
I can't seem to choose 32 bit. Any suggestions?
Setup:
Jriver>ASIO USB out m500

 

[Bigpond]

Welcome to the club. I have the same issue. It IS a ground loop and my suspicion is that this DAC is the culprit. .

Are you connecting all associated gear to the same outlet? Are you running from balanced to unbalanced? Have you tried running a ground wire from dac chassis to pre or amp chassis?

 

[Dexter_prog]

Are you connecting all associated gear to the same outlet? Are you running from balanced to unbalanced? Have you tried running a ground wire from dac chassis to pre or amp chassis?

All to same outlet. Unbalanced RCA (amp doesn't have balanced in), didn't try the ground wire (I'm scared my cat could grab it and get electrocutted somehow, silly?)

 

[BDWoody]

(I'm scared my cat could grab it and get electrocutted somehow, silly?)

Wouldn't want it to be electro-catted!

(My kids are shaking their heads and are telling people they are adopted)

 

[Dexter_prog]

Wouldn't want it to be electro-catted!

(My kids are shaking their heads and are telling people they are adopted)

hnaha nice one! Actually, today an electrician came to check everything. We did try grounding the PC's chasis to the DAC's chjasis and the hum went down... there's definitely some grounding issues with this unit, or maybe it isn't grounded at all?

 

[somy]

Hi, Anybody uses M500 and Hifiman Sundara/ananda combination? If so what do you think of the combo?

 

[Roddy]

Hey. New owner, but I've got a M100.

SW 1.6, HW 1.3, 2020-3-2 (2 March or 3 Feb?). "Speakers (SMSL USB DAC)" in Windows Audio.

To my surprise there's a SW 1.7. Given all the issues I read about, especially with updates on HW 1.2 , should I update to 1.7? Seems like a recipe for disaster. If I did, how would I go about doing it? I managed to get everything running, although I had to reinstall the Xmos USB driver. Seems to play well alongside the TUSBAudio one for the M100.

Is the screen OLED or LCD? Because I'm worried about burn-in if it's an OLED. And this is a pet peeve, but I noticed (thanks to dimming the display) that the light bleeds onto the IR sensor, which made me think it was lighting up. Shame there's no barrier to stop that.

And when I switch from line out to headphone out, I hear an audible click. That's a little worrying. In any other sector, hardware switches are the first to go. I keep my headphones plugged in constantly to avoid wearing out the jack. Should I be worried about wearing out the switch from too much switching? Guess I can't do anything about it. Why is it physical?